Combustion gas flow restricting member



P 1956 M. w. BARNES 2,762,322

COMBUSTION GAS FLOW RESTRICTING MEMBER Filed Oct. 5, 1950 FIE- 1 INVENTORI MARION W. BARNES CM )7. wai $022 AT TOR NEYS United tates Patent COMBUSTION GAS FLOW RESTRICTIN G IVIEMBE'R Marion W. Barnes, Wilmette, Ill., assignor to Universal Oil Products Company, Chicago, 111., a corporation of Delaware Application October 3, 1950, Serial No. 188.223

6 Claims. (Cl. 110-98) This invention relates to an improved and simplified form of gas restricting and heat radiating member for use between horizontally positioned and spaced fluid conduits in a heating chamber. More particularly the invention provides improved members adapted to restrict the cross-sectional area of the convection heating section of a furnace or heater and thus increase the mass velocity of the heating gas stream, to in turn improve the heating of fluids within the tubes comprising the convection bank.

In many cases relatively wide horizontal plates or baflie members are placed in a staggered arrangement across the upper portion of the box type or rectangular form of updraft heater to effect a restricting of the crosssectional area thereof and an increase in the velocity of the combustion and flue gas stream. The transfer of heat to the fluid conduits of the heater is proportional to the mass velocity of the heating gas stream, with an increase in the mass velocity of the heating gases effecting an increase in the rate of heating the fluid streams in the conduits. However, when relatively wide plates are used to baflie the gas stream, and they extend over several fluid conduits, there is not a uniform flow of gases past each conduit of the tube bank and optimum heating is not obtained.

It is therefore a principal object of the present invention to provide an improved type of heating gas restricting member which provides a more desirable and uniform means for increasing mass velocity of the heating stream between fluid conduits.

It is a further object of the invention to provide a heating gas flow restricting means, which not only uniformly restricts and battles the gas flow between fluid conduits in the convection heating section of. a heater, but in addition provides longitudinal members which can radiate heat to adjacent fluid conduits.

A still further object of the invention is to provide a relatively simple and inexpensive form of flow restricting and heat radiating member which may be fabricated from sheet metal and supported from one or more of the adjacent fluid conduits.

Briefly, the improved gas flow restricting member of this invention comprises an elongated tubular section having a wedge-shaped cross-section and adapted to extend centrally between horizontally positioned fluid conduits of a heater, and a plurality of hook-like hangers spaced along the tubular section suitable to support the latter from at least one adjacent fluid conduit.

The elongated wedge-shaped members may be of solid construction, however, they are preferably of tubular form and fabricated from metal sheets or plates. The material need not be heavy and is preferably of a gauge having a thickness of less than Vs". The sheets of steel may thus be bent and formed into a wedge shape by an ordinary sheet metal shop break, which makes longitudinal bends in the material.

The desired cross-section of the tubular members is described as wedge-shaped so that when the member is in proper position between fluid conduits, the lower edge ice will serve to slip the rising combustion gas stream and deflect it around each of the adjacent conduits at an increased velocity. However, the design may be varied to some extent and is not limited to a fixed cross-section. In other words the shape may be triangular with a pointed lower edge or may be trapezoidal, with a relatively narrow lower edge as compared with a wider top surface. The width and overall size will also vary in accordance with the spacing of fluid conduits or tubes within the heater.

Hook-like rods or hangers may be spaced along and extend from the top of each of the tubular restricting members in a manner permitting each of the latter to be suspended from a tube in the row next above. This construction is desirable when the heater tubes or fluid conduits are in rows having a staggered arrangement of tubes. In an alternative type of construction, the hangers or supporting rods may extend each way from the elongated flow restricting members and hold the latter in a midway position between conduits, by hooking over each adjacent conduit. This construction is desirable for holding the flow restricting members between fluid conduits in a top row, or where the conduits are not placed in rows having a staggered arrangement of tubes.

Reference to the accompanying drawing and the following description thereof will serve to more clearly show the design and construction of the improved flow restricting members, as well as point out further advantages and benefits for improving heating within the convection tubes of a heater.

Figure 1 of the drawing shows diagrammatically and in sectional elevation view, an updraft type of heater with a plurality of the improved restricting members suspended vbetween the convection tubes.

Figure 2 of the drawing shows diagrammatically, in cross-section, one form of flow restricting and heat radiating member.

Figure 3 of the drawing shows in section an optional form of the improved type of member.

Referring now to the Figure 1 of the drawing, there is shown diagrammatically the refractory walls or enclosure 1 for a typical form of small rectangular or box type of updraft heater. The heater has oil or gas burners, such as 2 at the ends thereof, suitable to supply flame and hot combustion gases for eifecting the heating of oil or other fluid medium within the horizontally disposed conduits. A plurality of wall tubes 3 and 3' are positioned along each interior wall of the chamber 1 in a manner to receive radiant heating from the flame of burnersZ. In the upper portion of the heater are a plurality of convection tubes in a bank 4. The tubes or conduits of the bank 4 are in horizontal rows, with a staggered arrangement of conduits being effected vertically. These tubes 4 are placed all the way across the heater 1 such that they receive convection heating from the hot combustion gases passing upwardly thru the heater and out by way of the breaching or stack 5.

In accordance with a present invention, a plurality of flow restricting members 6 are placed in the tube bank, one member between each pair of adjacent fluid conduits in each of the rows. Each of the members 6 is wedgeshaped and thus serves to restrict and deflect the heating gas flow around each tube, providing an increase in the gas flow rate. As hereinbefore noted, it is desirable to increase the mass velocity of the heating gases and effect a corresponding increase in the rate of heating the fluid medium within each of the tubes of the convection bank.

Figure 2 of the drawing shows to better advantage one method of constructing such gas deflecting and flow restricting members, and means for supporting them between the heater conduits. The wedge-shaped section 7 is preferably of longitudinal and tubular form, being formed of relatively light weight plate or sheet metal. The present embodiment is of a triangular shape with a lap in the sheet metal at one corner. This shape may be formed in a sheet metal break, and the lap may be spot-welded, riveted, or otherwise 'fastened to provide a rigid member. The tubular members 7 maybe as long as each of the fluid conduits 4, however, they need not be of thatlength, for two or more of the members may be placed end to end to accommodate the full length of the heater chamber.

Two or more hangers or bent support rods 8 are attached .to the upper face of the wedge-shaped member '7, so that means is provided for hanging the latter between tubes. This centered hanger construction is of course only utilized where the heater tubes or conduits are staggered as shown. Where the heater tubes are not staggered, other forms of hooks or supporting rods may be used. Reference to Figure 3 of the drawing shows a modified wedge-shaped section 9 with a plurality of supporting rods 10 extending across the top thereof in a manner suitable to hold each member longitudinally between the fluid conduits or tubes of the heater. These rods 19 may be welded or otherwise attached to the section 9.

The member 9 in this embodiment is of a trapezoidal shape, but, in a. manner similar to the action of the triangular sections 7, the members are all adapted to be supported centrally between fluid conduits and provide the desired restricting of flow of the heating gas stream, Other modifications in shape or form may of course be made. For example an oval or wedge-shaped member having concave or convex sides may be used to advantage. in addition, other forms of hooks or rods may be provided to extend from the tubular sections to maintain the desired positioning thereof.

It may be again pointed out that the wedge-shaped type of flow restricting members, as provided by this invention, not only increases the rate of flow of the hot combustion gases, but each one provides .a pair ofheating surfaces, comprising the sides of the members, which pick up and radiate heat to the adjacent surfaces of the heater tubes.

I claim as my invention:

1. In a heating chamber having horizontally spaced, horizontal fluid'heating conduits, the combination of gas flow restricting and heat radiating means comprising a horizontally elongated member of wedge-shaped cross section disposed between and in spaced relationship to adjacent fluid conduits in the heating chamber, said member being wider at its top than at its bottom and having inwardly tapering side walls extending from the horizontal plane of the bottoms of said adjacent tubes to the horizontal plane ofthe tops of said adjacent tubes, and a plurality of'longitudinally spaced hangers extending from said member and supporting the latter from at least one of the conduits in said chamber.

2. In a heating chamber having horizontally spaced, horizontal fluid heating conduits, the combination of gas flow restricting and heat radiating means comprising a horizontally elongated tubular member disposed between and in spaced relationship to adjacent fluid conduits in said chamber and formed of sheet metal and having a wedge-shaped cross-section, said member being wider at its top than at its bottom and having inwardly tapering side walls extending from the horizontal plane of the bottoms of-said adjacent tubes to the horizontal plane of the tops of said adjacent tubes, and a plurality of longitudinally spaced hook-like hangers extending from the upper portion of :said member and supporting the latter from at least one of the conduits in said chamber.

3. The combination of claim 2 further characterized in that said wedge-shaped tubular member has a triangular cross-section.

4. The combination of claim 2 further characterized in that said wedge-shaped tubular member has a trapezoidal cross-section.

5. In a heating chamber, the combination of at least two vertically spaced horizontal rows of horizontal fluid heating conduits, the conduits of the uppermost row being in staggered relation with those of the next lower row, a horizontally elongated member of wedge-shaped cross-section disposed between and in spaced relationship to adjacent conduits of said uppermost row, longitudinally spaced hangers extending laterally from both sides of said member and resting upon said adjacent conduits for supporting the wedge-shaped member from the lastnamed conduits, a second horizontally elongated member of wedge-shaped cross-section disposed between and in spaced relationship to adjacent conduits of said next lower row, and longitudinally spaced hook-like hangers extending upwardly from said second member and supporting the latter -from one of said adjacent conduits of the uppermost row.

6. In a heating chamber, the combination of at least two vertically spaced horizontal rows of horizontal fluid heating conduits, the conduits of an upper row being in staggered relation with those of the next lower row, a horizontally elongated member of wedge-shaped crosssection disposed between and in spaced relationship to adjacent conduits of said next lower row, and longitudinally spaced hook-like hangers extending upwardly from said member and supporting the latter from one of the conduits of said upper row.

References Cited in the tile of this patent UNITED STATES PATENTS 411,882 Baird Oct. 1, 1889 559,021 Baker Apr. 28, 1896 955,871 Hamann Apr. 26, 1910 1,334,937 Burton Mar. 33, 1920 2,363,267 Schauble Nov. 21, 1944 FOREIGN PATENTS 4,033 Great Britain Aug. 20, 1883 472,745 Germany Mar. 8, 1929 nil- 

